Field of the Invention
The present invention relates to a storage medium storing an image processing program and an image processing apparatus. The present invention particularly relates to a storage medium, which stores an image processing program for placing and displaying an image on a designated placement position, and an image processing apparatus.
Description of the Background Art
Conventionally, an image processing apparatus for enlarging/reducing an image in accordance with a distance between an input device and imaging targets (markers) is disclosed by Japanese Laid-Open Patent Publication No. 2007-236697 (hereinafter, referred to as Patent Document 1), for example. In the image processing apparatus disclosed by Patent Document 1, a controller has an image-pickup device for taking an image of two markers, and based on a distance between the two markers in the taken image, the distance between the input device and imaging targets (i.e., the markers) is calculated. Then, an image is: enlarged/reduced based on the calculated distance; placed on a position which corresponds to coordinates of a middle point between the two markers (e.g., a position pointed by the controller); and then displayed on a display device.
However, as shown in FIGS. 20A and 20B, in the case of the image processing apparatus disclosed by Patent Document 1, operability deteriorates when an area within which an image can be moved is fixed for images respectively having different enlargement ratios. In FIG. 20A, an area within which coordinates Pims, which indicate a position of an image IMs having a relatively low enlargement ratio, can be moved (movable area) is set. In the example of FIG. 20A, the movable area is set such that when the image IMs moves to a farthest edge of the movable area, almost the entire image IMs is displayed on a display screen, and a part of the image IMs is outside the display screen.
In FIG. 20B, similarly to the case of the image IMs, a movable area of coordinates Pimb is set for an image IMb having a relatively high enlargement ratio. In this case, the movable area is set such that when the image IMb moves to a farthest edge of the movable area, ¼ of the image IMs is displayed within the display area, and ¾ of the image IMs is outside the display area. Thus, in the case where the image IMb having a relatively high enlargement ratio is moved, as compared to the case where the image IMs is moved, when the image IMb is moved to the farthest edge of the movable area, a large portion of the image IMb remains within the display screen, and therefore it is likely that a user wishes to move the image IMb further to the outside of the movable are. However, such a wish of the user cannot be met since the movable area is fixed, and this results in operability deterioration for the user.
In the case of setting, assuming that the image IMb is to be moved, the movable area so as to extend to the outside of the display area, it is conceivable that if the image IMs having a relatively low enlargement ratio is moved within the movable area having extended to the outside of the display area, the image IMs disappears from the display area, and is not displayed on the display screen. In such a case, the user is unable to know where the image IMs is positioned, and this causes deterioration in operability.
Further, in the case where the image, which is placed on the position corresponding to the coordinates of the middle point between the two markers, is displayed on the display device, there is a possibility that the position to be designated varies depending on the distance between the controller and the markers. To be specific, in the case where the controller is operated at a remote position from the markers, even if a direction of the image-pickup device of the controller (i.e., direction in which the controller is pointed) is slightly changed, the designated position changes greatly, as compared to a case where the controller is operated near the markers. In other words, even if the user performs a same operation by using the controller, a result of the operation varies depending on the distance from the markers.